Essential fungal CaYLR100w polypeptides, and methods of use

Abstract

The present invention provides essential fungal polynucleotides and their encoded polypeptides, homologues thereof and their uses. Additionally, the invention provides methods for the identification of essential polynucleotides and fungal strains which may be used for drug screening.

1. An isolated polypeptide consisting of a sequence selected from the group consisting of:
 (a) an isolated polypeptide consisting of amino acids 1 to 346 of SEQ ID NO:12; and 
 (b) an isolated polypeptide consisting of amino acids 2 to 346 of SEQ ID NO: 12; wherein said polypeptide has keto-steroid reductase activity. 
 
     
     
       2. The isolated polypeptide of  claim 1 , wherein said polypeptide is (a). 
     
     
       3. The isolated polypeptide of  claim 1 , wherein said polypeptide is (b). 
     
     
       4. An isolated polypeptide encoded by a polynucleotide consisting of nucleotides 1 to 1038 of SEQ ID NO:1. 
     
     
       5. An isolated polypeptide encoded by a polynucleotide consisting of nucleotides 4 to 1038 of SEQ ID NO:1. 
     
     
       6. An isolated polypeptide produced by a method comprising:
 (a) culturing an isolated recombinant host cell under conditions in which said polypeptide is expressed, wherein said recombinant host cell comprises a recombinant vector consisting of a polynucleotide sequence encoding the polypeptide of either  claim 4  or  claim 5  operably linked to a promoter at the 5′ end and operably linked to a stop codon at the 3′ end, wherein said vector comprises an origin of replication and a selectable marker; and 
 (b) recovering said polypeptide. 
 
     
     
       7. An isolated polypeptide consisting of an amino acid that is at least 95.0% identical to amino acids 1 to 346 of SEQ ID NO:12, wherein percent identity is calculated using a CLUSTALW global sequence alignment using default parameters, and wherein said polypeptide has keto-steroid reductase activity. 
     
     
       8. An isolated polypeptide consisting of at least 318 contiguous amino acids of SEQ ID NO: 12, wherein said polypeptide has keto-steroid reductase activity. 
     
     
       9. The isolated polypeptide of  claim 1  wherein said polypeptide is fused to the Fc domain of an immunoglobulin. 
     
     
       10. An isolated polypeptide consisting of amino acids 29 to 346 of SEQ ID NO:12. 
     
     
       11. An isolated polypeptide consisting of amino acids 1 to 318 of SEQ ID NO: 12.